Infection status of coronavirus disease 2019 cases and close contacts in Fuzhou, Fujian

ObjectiveTo analyze the infection status of coronavirus disease 2019 (COVID-19) cases and close contacts in Fuzhou, Fujian province, and evaluate the risk of infection and morbidity in different exposure mode.

MethodsDescriptive Epidemiology investigation of COVID-19 cases and close contacts was conducted to analyze the secondary attack rate (SAR) of COVID-19 in Fuzhou.

ResultsThe epidemic of COVID-19 in Fuzhou had three stages. A total of 1 159 close contacts were found, the SAR was 2.07% (24/1 159). The median of interval was 12 days (rang: 2–21 days). In the relationship between close contact and cases, the SAR in old people in nursing home was highest (28.57%), followed by that in family members (5.52%), medical staff (3.23%), relatives (2.41%) and colleagues/classmates (1.67%), respectively. The differences were significant ( χ²=534.376, P＜0.001). Among the contact ways, the SAR of nursing (nursing home) were highest (28.57% ), followed by that of living in same room (5.26%), medical care (3.23%), being guest (2.82%), living in same building (1.77%) and short talk or other contact in daily work (1.55%), respectively. The differences were significant ( χ²=575.075, P＜0.001). The median of incubation period was 5 days (rang: 1–12 days).

ConclusionCOVID-19 is highly contagious. Timely and strict quarantine should be conducted for close contacts, especially for those at high risk, to reduce the possibility of community transmission.